It’s a regional issue that’s been going on for thousands of years, with many sub-events.

Essentially, Israel has been stealing land from Palestine since it was first created as a nation. Separate from that, relations between Israel and Gaza, which is a Palestinian territory inside Israel, have been tense, and blew up when Hamas, which effectively governed Gaza, broke through the barricade keeping them hemmed in and killed/kidnapped a bunch of people in Israel proper.

Israel responded by flattening most of Gaza, and attacking people in many other parts of Palestine and taking more land.

Hamas is mostly backed/funded by the Iranian government.

Israel also attacked Syria and sent some settlers over the Syrian border, and attacked Lebanon, targeting Hezbolah-controlled border states; Hezbolah is also Iranian government-backed.

Israel then attacked Iran, and convinced the US to join them.

It’s worth noting that the current Israeli government is hard-right expansionist nationalist, and has been waiting for an excuse to do these things for a while now.

Isreal and the US attacked iran together.

In short, yes. It's a fairly complex issue, but not so complex that it can't be understood. The broader context is imperial control of the middle east and decolonization, while the narrower context is the post-Octeber 7th conflict and genocide in Gaza. Iran is one of the few countries in the region that doesn't have a collaborationist puppet government, and is the only middle eastern regional power left that opposes US/Israeli interests. Therefore, Iran is the only check left against Israel gobbling up Palestine, Lebanon, Syria, and so on.

A lot of this is literally ancient history, so I'll try to keep it brief. 2000 years ago, Judea was a Roman province, and after a couple unsuccessful revolts, the Romans expelled most of the Jews, leading to the Jewish diaspora. Rome converted to Christianity, then later Islam arose and the Muslims, coming out of Arabia, conquered the Roman portion of the middle east. The region was ruled by various Muslim empires, briefly Christian crusaders, and then the Ottoman empire. It's important to note that Islam had official legal toleration of Jews and Christians (though this varied from time to time, with periods of repression), so there were always Christian and Jewish minorities in the middle east after the Muslim conquest.

In the 19th century, modern zionism, with many European Jews advocating the creation of a Jewish state. This was a secular and self-consciously colonial project based on 18th century theories of ethnic nationalism rather than being overtly religious. They thought they could solve what they saw as the "problems" with the Jewish diaspora - the "rootless, weak, overly-intellecutal" Jew would be replaced with a new "muscle Jew" who is strong, confident, athletic, and rooted to the land. If this sounds a bit like Nazi rhetoric, it's because it came from the same milieu of European antisemitism that Nazism came from.

The Zionists weren't set on the holy land - as I mentioned, it was a secular project. They would have gone for Uganda, Cyprus, or a number of other places. A major impetus for selecting Palestine was the Balfour declaration of 1917, in which the British declared that a Jewish state would be created in Palestine (at the time still part of the Ottoman Empire). With the conclusion of WW1, the Ottoman Empire was partitioned between France and Britain, with Palestine being administeded under the British Mandate. Through the interwar period, zionists immigrated to Palestine, often buying land from absentee landlords and evicting the tenants. This caused conflict, naturally, and the Jewish colonists were often used as auxiliaries by the nominally neutral British in order to keep the Arabs down. This was a classic British imperial strategy in which they would use a minority against a majority, ensuring the minority was dependent on them.

Another major impetus to the zionist project was of course WW2 and the Holocaust, though it doesn't play as major a role as the Israelis would say. In fact, the Jews murdered in the Holocaust were that very "weak, rootless, overly-intellectual" diaspora Jew that the Zionists wanted to replace. It did lead to another wave of Jewish immigration to Palestine, but the zionists there had contempt for the holocaust victims, calling them "soap" - the zionists figured that they would have fought back rather than being "weak victims."

The conflict reached a boiling point in 1948 and became an open civil war between Jews and Arabs, and later an international conflict. The Israelis ended up winning, and during and after what they call their independence war, they killed or displaced about half of Palestine's majority Arab population in the Nakba. The reasoning for this killing and displacement at a basic level was that Israel was to be a Jewish majority state, and having too many Arabs (who were the majority, remember) would compromise the Jewish nature of the state. They didn't have to get rid of all of them, and indeed it was useful to keep an Arab minority as a fig leaf to make it appear as if Israel was just a normal democracy rather than an ethnic-supremacist project.

The following decades saw more wars, with Israel annexing parts of Syria, and briefly Egypt. The surrounding Arab states rightly saw Israel as an invader and a colonial outpost - remember that this was the period of decolonization, where the European empires lost their overseas territories, but here was a Soth African or Rhodesian-style European colonial project in their midst. However, Israeli battlefield successes combined with increasing American support saw the neutering of most of the Arab regimes. Post-colonial nationalism gave way to neo-colonial puppetry by the United States. At the same time, Israel continued to take more land in occupied Palestine, with extremist settlers driving Palestinians out of their homes in the West Bank. Repeated uprisings by the Palestinians only further radicalized the Israelis, and by the time of October 7th, 2023, the Palestinian parts of the West Bank were a series of walled-off towns connected by Israeli-controlled highways with multiple checkpoints at which Palestinians could be stopped at any time for any reason (and they have colour coded license plates to make this easier). A de-facto system of racial segregation.

As I mentioned previously, the Arab regimes in the area had been neutered and rendered pliant by American money and support. The rich gulf states were only interested in enriching themselves further, and the Egyptian military dictatorship was only interested in securing its position and looting the country. The only country willing and capable of acting as a counterbalance to Israel was Iran, along with various militias and paramilitaries, but Iran wasn't willing to risk a direct confrontation with the US and Israel, preferring a mix of proxy war, deterrence, and diplomacy.

With all of the Arab states moving toward normalization and their only real allies unwilling to directly confront Israel and the US, Hamas leader Yahya Sinwarknew that it was now or never. Israel would slowly eat more and more of Palestine until there was nothing left unless they forced that confrontation, so they planned and executed a brilliant raid into Israel, successfully attacking military installations and taking prisoners to exchange for their own prisoners (note that Israel, while they whined about the hostages, kept a far greater number of Palestinians in prison without trial and in worse conditions), in the hopes that it would set off a massive confrontation that would lead to their liberation. Israel responded by bombing Gaza to rubble and blockading all food, water, and medicine, with the aim of starving them out and desteroying them once and for all, and with Gaza taken care of, the isolated and fractured West Bank could be dealt with piecemeal.

While there was a (partial) ceasefire, and Iran had never fully committed during the previous phase of the conflict, Israel had become radicalized and emboldened to see its own plans through. They wanted Iran and Hezbollah gone so that they could eat up Palestine without resistance, annex Lebanon, and keep expanding. Israel does not have defined borders, and the most extreme Israelis (who are ascendant) have a dream of a greater Israel that includes parts of Syria, Iraq, Saudi Arabia, and so on. To achieve this, they needed Iran out of the picture, and to get rid of Iran they needed the help of the United States.

So, at the beginning of March, amidst civil unrest in Iran (partially organic, partially caused by US economic warfare, partially direct actions of Israeli intelligence agencies) they took their shot. Aiming to fracture Iran into dozens of unstable and weak states that could never oppose them, they and the US assassinated top Iranian leadership in a surprise attack, using supposed negotiations as cover. Iran had planned for this contingency, and they unleashed their ballistic missiles and drones on American targets all over the gulf, destroying a large portion of America's air defences and early warning radars and allowing them to strike directly at Israel with minimal warning. Despite the present semi-ceasefire, nothing has been resolved as Iran has no reason to see the US or Israel as trustworthy negotiators, and any peace deal would likely just end with another attack on them in 6 months to a year. So, the strait of Hormuz remains closed, Iran still has a knife at the throat of the global economy, and they can't afford to show any weakness - they have to cause the US enough pain that they will be forced to the negotiating table in good faith, and force the US to pull Israel's leash. At the same time, the US won't admit defeat, and Trump's plan is to declare a double-blockade on Iranian shipping and pretend like they're winning.

I don't see this ceasefire holding much longer, and I expect the war will go hot soon enough, maybe in only a few days. What ultimately ties the Palestinian and Iranian sides of this conflict (aside from religious sympathies) is the fact that Israel is a tool America uses to keep control over the Middle East, while Israel for its part has practically unlimited territorial ambitions and needs to continually expand in order to secure buffer zones against what they see as their hostile neighbours, and then secure further buffer zones to protect those buffer zones (which are now settlements) and so on.

Iran has backed Hezbollah and Hamas by providing weapons and funds, and after the October 7 attacks by Hamas, fired some ballistic missiles at Israel.

So in that sense, yes, they're linked.

However, that's also not the only factor involved

that is, this isn't just "Israel and Palestine fight, ergo Iran conflict". Iran wants to develop nuclear weapons, which is an issue for the US. There's been historic conflict between Iran and the US on a number of different issues, from the Shah to Iran involving itself in the US conflict in Iraq, providing weapons to the Houthis, etc.

EDIT:

Here: Wikipedia: Iran-United States relations

Yes, they're related. Iran was threatening to attack and even invade Israel soon after the genocide began. They've been supplying Hamas and Hezbollah for years. Israel thinks it has Hamas on the run and decided to start going after a bigger threat while they still had Trump in their back pocket.